“Given that ethanol is an increasingly important factor in the cost and supply of motor fuel in the U.S., it is critical that the Committee have a better understanding of the causes and effects of RIN market volatility and developments,” Wyden and Murkowski wrote in a letter to EPA Acting Administrator Robert Perciasepe.

As part of preparation for a hearing on gasoline prices later this spring, Wyden asked the EPA to provide data concerning RINs market volatility and irregular trading, deficits and surpluses in RINs carried over from the previous year, as well as production and consumption of biofuels in the United States.

Refiners are required to blend 13.8 billion gallons of ethanol into the U.S. gasoline supply this year. Prices for conventional RINs rose from $0.07 at the beginning of January to $1.10 during the first week of March. Fuel blenders and refiners use RINs to meet the national requirement for biofuels under the Renewable Fuel Standard.